Machine and method of producing loop pile fabrics for use as floor covering



PARLIN March 3, 1959 MACHINE AND METHOD OF PRODUCING LOOP FILE:

FABRICS FOR USE AS FLOOR COVERING 1 3 Sheets-Sheet 1 Original Filed May 20, 1952 I 10 [IE Me 15 ma 150 15a la v 70 g4 86 60 I Q14 H l I 66 "I :52: I" JILL-.115 0 68- f' ,1 ,1 a: 84 170 9 /a4{ /7! a i\\\\ mm- 96 I 8& 5e 74 Ii'wenfoz' flm Ib B Par/[n 9 211E421:

' March 3, 1959 D. B. PARLIN 2,876,183

. MACHINE AND METHOD OF PRODUCING LOOP FILE FABRICS FOR USE AS FLOOR COVERING Original Filed May 20, 1952 3 Sheets-Sheet 2 lav ' lea I I ma ,J-l 7 1', l I 5 I60 6 U, L

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MACHINE AND METHOD OF PRODUCING LOOP FILE FABRICS FOR USE AS FLOOR COVERING Original Filed May 20, 1952 5 Sheets-Sheet 3 am am M 1 v p P fla /'0 Par/177 2% W52:

flitiod aey Unitgd tates Patent MACHINE AND METHOD OF PRODUCING LOOP PILE FABRICS FOR USE AS FLOOR COVERING David B. Parlin, Thompsonville, Conn., assignor, by mesne assignments, to TuftedPatterns, Inc., Atlanta, Ga., a corporation of Georgia Original application May 20, 1952, Serial No. 288,823. Divided and this application January 15, 1954, Serial No. 404,243

6 Claims. (Cl. 112-79 The present invention relates to improvements in drawn loop pile fabric, and more particularly to an improved machine and method for producing such fabrics for use as floor covering.

The present application is a division of my copending application, Serial No. 288,823, filed May 20, 1952, now abandoned, for Manufacture of Drawn Loop Pile Fabric.

In the manufacture of drawn loop pile fabrics, such as cotton rugs for use as floor covering, a layer or sheet of backing material, such as a woven fabric, is fed to a tufting machine which may consist of a group of pile yarn carrying needles and a group of cooperating loopers, the needles acting to insert loops of pile through the backing material from the bottom to theface side where they are caught and held by the loopers while the needles .are withdrawn through the backing fabric. Upon the advancing or work piercing stroke of the needle the pile yarn is drawn from the yarn supply, reeving through the needle eye. Upon the subsequent retracting movement of the needle, the loop of needle yarn, againreeving through the needle eye, is tightened against the looper which thus controls the height of the loop above the face of the backing material. Accordingly the legs of the pile loops pass completely through the backing fabric without interweaving with the strands of the backing fabric, as contrasted with woven carpets and rugs in which thelegs of the pile loops are interwoven with the backing and thus secured thereto.

In accordance with the present invention it is proposed to vary the height of the individual loops or tufts in accordance with a prearranged pattern which may be arranged to produce a desired pattern in the pile surface of the rug.

In the form of the invention illustrated, a controlled variation in the height of the individual loops of yarn is produced by means of a controlled variation of the tension placed on the yarn feeding from the yarn sup- -ply. Specifically, it has been found that an increase in the tension placed on the yarn, or alternatively 'by a positive arrest of the feeding yarn during at least a portion of the loop-advancing movement of the needle, will cause yarn to be drawn from the preceding loop for the formation of the new needle loop so that the preceding loop in the series formed with the same yarn can be reducedin size to any desired extent.

A tufting machine for producing floor coverings which embodies in a preferrel form-the severalfeatures of the invention, and the several steps of the method which is {employed in accordance with the invention'for producing floor coverings are hereinafter described in connection with the accompanying drawings in which: Fig. 1 is a plan view of a tuftingmachineembodying in preferred form the several features of the invention; Fig. 2 is a view in elevation of the tufting machine illustrated in Fig. 1; Fig. 3 is an elevation, partly broken away, of parts shown in Fig. 2 looking from the left; Fig. 4 is 'adiagra'rnmatic view illustrating 'the electricalcontr'ol system including the tension controhsole'noids pattern 2,876,183 Patented Mar. 3,

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cams and switch connections controlled thereby for prov du'cing a pattern of long and 'short loops in the floor covering; Fig. 5 is a a plan view of a floor covering constructed in accordance with the invention; Fig. 6 is a detail sectional view of the fabric shown in Fig. 5; Fig. 7 is an enlarged detail view of one of the yarn tensionin'g devices shown in Fig. 3, the tensioning plunger of the device having been extended to apply a tensioning bend to the feeding yarn; Fig. 8 is a view similar to Fig. 7 but with the plungerwithdrawn to release the tension being applied in Fig. -7; Fig. 9 is a diagrammatic view showing the newly formed loop or tuft, and the needle as it is retracted from the work; Fig. 10 is a diagrammatic view of the needle and looper assembly showing the needle advanced through the work to form the next succeeding loop, and illustrating the manner in which yarn is robbed from the previously formed loop; Fig. 11 is a viewof the parts as shown in Fig. 10 looking from the left; Figs. 12 and 13 show a modification in which the feeding yarn is positively arrested'during a portion of each cycle, Fig. 12 showing-the plunger adv'ancedto arrest the'feeding yarn and Fig. 13 showing the *plungerwithdrawn to release the-feeding yarn; Fig. 14 'is a detail view showing an-alternative arrangement of the plunger, whereby each of the three air valves shown is adapted' for controlling -the tension on 'two feeding yarns,the plunger beingshown inits advanced position to apply a tensioning strain on two yarns; and Fig. 15 is aview similar tO-Fig. 14, but with the. plunger withdrawn to release the-feeding yarns.

Referring to the drawings, a'portion of a floor cover ing orrug'is shown which is of the general-type comprising a backing material through which are drawn series of loops fromfeedin'gpile yarns to for'malooped pile surface. An adhesive may be applied to the back of the backing material-subsequently in order to bind the pile loops in the fabric and to :prevent pulling -or snagging of individual loops when the rug is in -use. Floor coverings of this general character in which the loops are uniform in height are Well knownin the art.

In accordance with thejinvention, selected loops from the series formed from-any individual -feeding yarn are made of reduced length so that a pattern of long and short loops of controlled length is formed in the pile face of the floor covering.

Referring specifically to Fig. -5, the backing material ofthe floor covering or rug is indicated at 20, and parallelrows'of loopswhich are "serially formed from individual feeding yarns are indicated at 22, -24, '26, 28 and 29. While onlya small fragment of a pile surface floor'covering is shown-'itis understood that the number of feeding yarns and parallel rows-produced thereby may be increased to produce a pile surface floor covering ofany desired size.

In accordance with the invention, an improved form of a pile surface floor covering is provided in which selected loo'ps formed fromfany selected feeding yarn are made alternatively ofeither-anorinal or'aless than normal height so that a design of long and of shorter loops is formed in the pile surface of the floor covering.

As shown specifically in Fig. 6'of the drawings, 'loops 22 and 24 formed from the feeding yarn 30 are of normal length. Loops 2'6, 28 and 29 formed from the feeding yarn 30 have been shortened in accordance with the novel method hereinafter described and appear in the pile surface as portions of a ground pattern of shorter loops. It will be understood that the novelty of a'ppli cants improved floor covering is not limited to any specific design of long and short loops, but is capable of infinite variation in accordance with the selection of long "and short loops over the entire pile 'sur'faceof the floor v Q K I 1 U.

'3 covering-and with. variation'in the length of the short loops,

Further in accordance with the invention, a novel method is provided for producing selectively the long and, short loops in the'pile surface of the floor covering which consists specifically in forming each loop of a normal length, and thereafter when the floor covering design calls forshort loops, impeding the feed of yarn from the supply side of the needle during its loop drawing stroke so that the needle while advancing through the work is-forced to draw, or rob, a portion of the yarn for the new loop from the preceding loop, causing the preceding loop to be shortened. In one form of the invention the yarn feed is-positively arrested during a portion of the loop drawing cycle'so that a measured amount of yarn is drawn or robbed frorn the preceding loop. In another form of the invention the feed of the yarn from the yarn supply is impeded by means of yarn tensioning device which acts during the entire loop drawing cycle. The amount of the frictional resistance provided by the tensioning device isadjusted to cause a portion of the yarn forming the new loop to be drawn from or robbed from the preceding loop.

'='The method of positively arresting the feeding yarn during a portion of the loop-drawing cycle has the adva'ntage that the amount of yarn allowed for the new loop -and, therefore, the amount of yarn which will be robbed from thepreceding loop is accurately measured. The method of impeding the feed of the yarn by means of a yarn tensioning device has, however, been found most satisfactory for high speed operation of the tufting machine. A simple form of tensioncontrol has been found to. produce an extremely accurate regulation of loop length, making possiblethe formation of shorter loops which may be of uniform height or of different heights to produce a pattern of uniform and attractive appearance.

In carrying out the steps of applicants method of producing his improved tufted pile face floor covering, a tufting machine is provided which may be primarily of conventional construction. Referring specifically to Figs. -2 and 3 of the drawings, a six needle over-arm tufting machineis provided which comprises a base 36, a column 38 andan over-arm 40. The operating instrumentalities include a group of six eye pointed needles 42 rigidly secured tomove as a unit in holder 44 secured to the lower end of a needle bar 46 mounted for reciprocatory movement inthe over-arm 40. The needles are arranged to project through slots formed in a presser foot 48 mounted on a presser foot bar 50 supported for reciprocatory movement in the over-arm 40. Below the level of the presser foot the needles are arranged to project through holes formed in a feed plate or dog 52 supported from the base 36.

'Beneath the feed dog 52 there is provided a group of six hook shaped-loop measuring loopers 54 which are secured to a horizontally disposed looper rock shaft carried on the base 36.

The mechanism for operating the several cooperating instrumentalities of the tufting machine being of a type well known in the art will be briefly described in connection with Figs. 2. and 3 of the drawings in which is shown a main drive shaft 58 horizontally disposed within the over-arm40. The shaft 58 carries a hand wheel 60, and

a driving belt pulley 62 which is connected by a drive belt 64 with any convenient power source such as an electric motor not shown. At its forward end the drive shaft 58 is provided with a crank 66 which is connected by means of a link 68 with the needle bar 46. The looper rock shaft 56 is driven from the drive shaft 58 by means of an eccentric 70 on the main shaft 58 which is connected by a link 72 with a laterally extending offset arm 74 connected to the looper rock shaft 56. Vertical forward and back movements are imparted to the feed dog 52in timed relation with the needle movement through connections with the main .drive shaft. As

shown in Fig. 3, the feed dog is supported at its left end by means of vertically disposed lever arms 76 rigidly secured to a horizontal rock shaft 78 for imparting forward and back movements to the feed dog. The feed dog 52 is further supported at its right end by pin and slot connections with arms 80 secured to a rock shaft 82 horizontally disposed in the base 36 for moving the feed do vertically.

Rocking movements are imparted to the shafts 78 and 82 by means of connections from the main cam shaft 58 which comprise eccentrics 84 and 86 on the drive shaft 58, eccentric 84 being connected by means of an eccentric link 88 with a laterally extended arm 90 on the rock shaft 78. 1 The eccentric 86 is connected with the drive shaft 82 by means of an eccentric link 94 which connects with an offset arm 96 secured to drive shaft 82. The presser foot 48 above referred to is normally maintained yieldingly against the work by means of a compression spring 100 coiled around the presser foot bar 50 within the over-arm 40. Separate feeding yarns designated respectively at 102, 104, 106, 108, 110, and 112 are threaded into the individual needle eyes, being drawn from individual sources of supply which may be spools such as indicated at 114, Fig. 3, mounted on the spindle support 118 apart from the machine.

In the normal operation of the tufting machine a backing material is fed face down beneath the presser foot 48 and is given a stepped advancing movement with each operating cycle of the machine by the action of feed dog 52. The downward work piercing stroke of the needles 42 causes a loop of needle yarn to be drawn through the backing material. The loopers are now rocked to engage the needle loops, and the needles are then withdrawn, causing the loop to be tightened to a measured length determined by the depth of the looper beneath the face of the backing material. During this operation a light tension is maintained on the feeding yarn being drawn around the normally provided guides from supply, and/ or by the reeving action of the yarn through the needle eye.

In accordance with the invention, tensioning devices are provided which act upon selected yarns drawn from supply to prevent or to impede the feed of the warn during a portion at least of the loop forming cycle so that the needle during its downward loop drawing stroke is forced to draw yarn from the preceding stitch.

Referring to Figs. 1, 2, 3, 7 and 8, the yarns 102-412 inclusive are drawn from spools 114 over a guide roller 120 through a guide 122 to tension device 124 hereinafter to be more specifically described. From the tensioning device 124 the yarns extend downwardly through a guide plate 126 to their respective needles 42.

The tensioning device, in the preferred form shown in Figs. 1, 2, 7 and 8, comprises a tension control for each of the three yarns 104, 108 and 112, which takes the form of threeair cylinders 128, 130 and 132, respectively provided with air operated plungers 134, 136, and 138. The plungers extend horizontally between a series of upper guide arms and lower guide arms 142 carried on the supporting bracket for the tensioning device. Each of the guide arms 140, 142 and the air cylinder plungers 134, 136 and 138 are perforated to receive the feeding yarns. When an air cylinder plunger 134 is retracted as shown in Fig. 8 the yarn passes in a straight line through said perforations without any appreciable resistance. When a plunger 134 is advanced to the ofiset position, as shown in Fig. 7, a relatively sharp tensioning bend is introduced into the yarn so that a resistance is built up to the drawing off of the yarn from supply.

While in the form of the device shown in Figs. 1, 2, 3, 7 and 8, only the alternate yarns 104, 108 and 112, are subjected to a tensioning control, it will be understood that all of the yarns may be controlled either individually or in groups, as illustrated for example in Figs. 14 and 15, ,As shown in these figures, the tensioning device iiijfailitis transmits guide arms iii and 14$,ah ravin twoperforations, and each'ofthe cooperating air eylind'ers128, 130 and 132, is provided with air actuqatedplunger 148 similarly provided with twoape'rtures so that movement of each air actuated piston will cause thesimultaneous tensioning or release of two feeding yarns.

Inu the form of the invention shown, a pattern conthetension on selected feeding yarns and during selected loop drawing operations of the machine. The air cylinders 128, 130 and 132, are connected respectively by conduits150, 152 and 154 with solenoid operated air valves 156,158 and 160 to which air is supplied from any conynient source through an air pipe 162 and a usual arrangementof reducing and shut-off valves generally indicated at 164. The air cylinders and solenoid operated air valves, being commercial units, all of well known construction, have been illustrated in outline only. i

, The operation of the solenoid operated air valves and air cylinders above referred to is controlled by elec- .trolmechanism is provided for applying and for releasing trical means hereinafter more fully to be described, from a pattern device which as best shown in Figs. 1 and 2,

comprises a group of three pattern cams 166, 168 and 170 mounted on a pattern drum 172 driven ,in timed relationwith the main drive shaft 58 of the tufting machine. The connections through which the pattern drum .172 is driven comprises a sprocket 174 on the ,drive shaft 58 and a sprocket'chain 176 connecting withthe input sprocket 178 to a 10-1 ratio reduction gear box 18,0. The output sprocket 182 of the reduction gear ,boir 180 is connected by a chain 184 with a sprocket 186 on the pattern drum 172.

The electrical controls associated with the pattern mechanism above described, as best shown in the diagrammatic Fig. 4, consist of three microswitches 188, 190 and 192 having contact elements arranged to be acted upon by high portions of the respective pattern cams 166, 168 and 170. Each of said microswitches has one terminal thereof connected with a wire 194 which is arranged to be connected through a switch 1967with a supply wire L-2. The second terminal of microswitch 188 is connected by a wire 198 with the air valve actuating solenoid ,160. .The second contact of microswitch 190 is "portion of its actuating cam will energize the air valve solenoid connected therewith, opening the associated air valve, and causing the air piston plunger controlled thereby to be shifted to the offset yarn tensioning position of Fig. 7 or Fig. 14. The tensioning device may be maintained in a tensioning position through one or anumber of loop forming operations depending upon the contour of the actuating pattern cam on the drum 172.

The electrical connections illustrated in Fig. 4 may be readily adapted for operation with the feeding yarn arresting device of Figs. 12 and 13 -by moving switch 196 from the full line position of Fig. 4 to its alternate position in which the wire 194 is connected with a wire 206 which is in turn connected with a timing switch 208. A wire 210 is connected with the remaining terminal of timing switch 208 and with the main line wire L-2 to complete the circuit. The timing switch 208 is arranged to be acted upon by a switch actuating arm 212 which is periodically moved to close switch 208 by means of a timing cam 214 on the main drive shaft 58 of the machine. With the switch 196 in the right hand position connecting wires 194, 206 it will readily be appreciated that engagement at a microswitch 190 or 192 with a high portion of its actuating cam will close the circuit through the associated solenoids 156,

1 58 and during only that small portion of each operating cycle of the machine in which timing .switch 208 is closed by engagement of switch arm 212 with the high portion of the actuating cam 214.

As shown in Figs. 12 and 13, the air valve plunger 216 will be advanced by the admission of air under pressure to the air cylinder 128 so that the end of the plunger216 engages the feeding yarn 104 against a Soft rubber base 218 and thus frictionally. locks the feeding thread 104 against movement. In this embodiment of the inventionv the yarn tensioning plunger is in its advanced state duringa portion of the loop formingcycle which is determined by the constant timing cam 214, which is regulated to cause each preceding stitch formed while the plunger is in operation to be reduced to a predetermined shorter normal length. At a later point in the loop forming cycle the timing switch 208 opens causingthe solenoids 156, 158 and 160 to be deenergized and the associated air valves to be closed, so that the plungers 216 are permitted to return to the inoperative position of Fig. 13.

The timing of the closing and opening of the timing switch 208 is adjusted to cause the yarn feed to be arrested during a predetermined portion only of the advancing or loop drawing stroke of the needles 42 through the backing material, so that a portion of the yarn for the new loop is drawn from the preceding loop as .indicated by the dotted and full line positions for example in Fig. 10.

The invention having been described what is claimed 1. In the method of forming patterns with pilefloop s in a base fabric comprising simultaneously insertinga plurality of lengths of yarn through said fabri-c to a predetermined depth to produce a first series of loops aligned transversely of the line of feed, pulling from a supply an additional length of yarn to each of said lengths of yarn during a yarn feeding period for use in the formation of a second series of aligned loops and simultaneously inserting the additional lengths of yarn through said fabric to the said predetermined depth along a line spaced from the first series to form said second series of aligned loops, the step of furnishing according to a prescribed pattern a lesser length of yarn to at least one of the loops in the secondseries than to other loopsjin ;the second series, by stopping the feed of the yarnsof whicha lesser length is to be furnished before the end of said yarn feeding period, b y engaging them by clamping members while not so engaging the other yarns, at a point between said supply and said second series of loops, during the formation of said second series of loops, the said lesser length of yarn being insufiicient to form com pletely its loop in the second series to the said predetermined depth, whereby the corresponding loop in the first series is robbed of a part of its yarn and the height of the loops in the first series will vary according to the length of yarn furnished to its corresponding loop in the second series, and thereafter disengaging said clamping members from said yarns of which a lesser length is to be furnished.

2. In the method of forming patterns with pile loops in a base fabric comprising simultaneously inserting a plurality of transversely aligned loops through a base fabric to a uniform predetermined depth to form a first row of transversely aligned pile loops, pulling from a supply, during a yarn feeding period, yarn for the successive formation of additional rows of aligned loops spaced from and generally parallel to said first row of loops, and repeating said loop-forming operation; the step of stopping the feed of selected yarns before the end of the feeding period by engaging them by clamping members while not so engaging the other yarns, at a point between said supply and said second row of loops during the formation of said second row of loops and thereby backdrawing yarn in an amount corresponding to the demands of a prescribed pattern from pile loops in said selected yarns andin said first formed row of loops into corresponding loops in the second row of loops during their formation to thereby shorten the selected loops in said first formed row of loops in an amount corresponding to the length of yarn backdrawn therefrom, while avoiding backdrawing yarn from the other loops in the said first row, and thereafter disengaging said clamping members from said yarns of which a lesser length is to be furnished.

3. In themethod of forming patterns with pile loops in a base fabric comprising simultaneously inserting a plurality of lengths of yarn through said fabric to a predetermined depth to produce a first series of loops aligned transversely of the line of'feed, pulling from a supply along a normal path an additional length of yarn to each of'said lengths of yarn during a yarn feeding period for use in the formation of a second series of aligned loops and simultaneously inserting the additional lengths of yarn through said fabric to the said predetermined depth along a line'spaced from the first series to form said second series of aligned loops, the step of furnish- I ing according to a prescribed pattern a lesser length of yarn to at least one of the loops in the second series than to other loops in the second series, by drawing a portion of the yarns of which a lesser length'is to be first serieswill'vary according to the length of yarn furnished to its corresponding loop in the second series,

4. In the method of forming patterns with pile loops in a base fabric comprising simultaneously inserting a plurality of transversely aligned loops through a base {fabric to a uniform predetermined depth to form a first row of transversely aligned pile loops, pulling from a supply along a normal path during a yarn feeding period yarn for the successive formation of additional rows of aligned loops spaced from and generally parallel to said first row of loops, and repeating said loop-forming operation; the. step of drawing a portion of selected yarns outside said normal path thereby increasing the resistance to the pulling of said yarns between said supply and said second row of loops during the formation of said second row of loops and before the end of the yarn feeding period and thereby backdrawing yarn in an amount corresponding to the demands of a prescribed pattern from pile loops in said selected yarns and in said first formed row of loops into corresponding loops in 'fabricby the needles to 'form loops, means for engaging and disengaging selected yarns comprising clamping means located at a point between said supply and said needles during the formation of the loops and before the needles reach the bottom of their stroke to positively arrest the drawing of the selected yarns from said supply when so engaged and cause the needles to backdraw yarn from loops previously formed in said selected yarns during the time that it takes the needles to reach the bottom of their stroke, and control means for rendering said clamping means operative to engage and inoperative to disengage said yarns in accordance with a pattern to produce a selection of loops shorter than other loops in said base fabric.

6. In a tufting machine having a yarn supply and a plurality of reciprocating needles for drawing yarns along a normal path from the supply and inserting them into a base fabric, means for releasably holding the yarns inserted into the base fabric by the needles to form loops, a plurality of tensioning devices adapted to draw portions of selected yarns out of said normal path to form tensioning bends therein at a point between said supply and said needles during the formation of the loops and before the needles reach the bottom of their stroke to cause the needles to backdraw yarn from loops previously formed in said selected yarns during the time that it takes the needles to reach the bottom of their stroke, and control means for rendering said tensioning devices operative and inoperative in accordance with a pattern to produce a selection of loops shorter than other loops in said base fabric.

References Cited in the file of this patent UNITED STATES PATENTS 876,562 Kleutgen Jan. 14, 1908 982,234 Blair Jan. 24, 1911 1,064,406 Ward et a1. June 10, 1913 1,831,485 Dykeman Nov. 10, 1931 1,863,049 Hermann June 14, 1932 1,909,531 Gladish May 16, 1933 2,354,731 Ashworth et a1 Aug- 1, 1944 2,784,689 MacCatfray Mar. 12, 1957 

1. IN THE METHOD OF FORMING PATTERNS WITH PILE LOOPS IN A BASE FABRIC COMPRISING SIMULTANEOUSLY INSERTING A PLURALITY OF LENGTHS OF YARN THROUGH SAID FABRIC TO A PREDETERMINED DEPTH TO PRODUCE A FIRST SERIES OF LOOPS ALIGNED TRANSVERSELY OF THE LINE OF FEED, PULLING FROM A SUPPLY AN ADDITIONAL LENGTH OF YARN TO EACH OF SAID LENGTHS OF YARN DURING A YARN FEEDING PERIOD FOR USE IN THE FORMATION OF A SECOND SERIES OF ALIGNED LOOPS AND SIMULTANEOUSLY INSERTING THE ADDITIONAL LENGTHS OF YARN THROUGH SAID FABRIC TO THE SAID PREDETERMINED DEPTH ALONG A LINE SPACED FROM THE FIRST SERIES TO FORM SAID SECOND SERIES OF ALIGNED LOOPS, THE STEP OF FURNISHING ACCORDING TO A PRESCRIBED PATTERN A LESSER LENGTH OF YARN TO AT LEAST ONE OF THE LOOPS IN THE SECOND SERIES THAN TO OTHER LOOPS INC.P THE SECOND SERIES, BY STOPPING THE FEED OF THE YARNS OF WHICH A LESSER LENGTH IS TO BE FURNISHED BEFORE THE END OF SAID YARN FEEDING PERIOD, BY ENGAGING THEM BY CLAMPING MEMBERS WHILE NOT SO ENGAGING THE OTHER YARNS, AT A POINT BETWEEN SAID SUPPLY SAID SECOND SERIES OF LOOPS. DURING THE FORMATION OF SAID SECOND SERIES OF LOOPS, THE SAID LESSER LENGTH OF YERN BEING INSUFFICENT TO FORM COMPLETELY ITS LOOP IN THE SECOND SERIES TO THE SAID PREDETER MINED DEPTH, WHEREBY THE CORRESPONDING LOOP IN THE FIRST SERIES ID ROBBED OF A PART OF ITS YARN AND THE HIGHT OF THE LOOPS IN THE FIRST ERIES WILL VARY ACCORDING TO THE LENGTH OF YARN FURNISHED TO ITS CORRESPONDING LOOP IN THE SECOND SERIES, AND THEREAFTE DISENGAGING SAID CLAMPING MEMBERS FROM SAID YARNS AF WHICH A LESSER LENGTH IS TO BE FURNISHED. 